512 stroker.
i did that exact kit! the race shop i used back home was very impressed with the quality of the product for the price!
i went with the eddy Victors... flow the same as a hemi out of the box (325) and cost less than the indy stuff (which is to big for the street)
what are your plans for the build and what you are going to do with it??
also they will switch out to KB pistons to little or no charge...